Sina Corp. issued an apology to users of its Weibo service after it was hit by a virus, in what appeared to be the first attack of its kind against the popular Chinese microblogging service.

The attack began around 8:20 p.m. Tuesday when malicious links advertising videos, updates on scandals and other eye-catching content began appearing on Weibo, a Twitter-like service that had more than 140 million users as of March. The virus infected the account of any user who clicked on one of the links, prompting it to send out links to the user’s followers.

“We deeply regret the inconvenience experienced by some users” as a result of the attack, Sina said in a statement posted Wednesday on the company’s website.

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Local media reports estimated the number of accounts infected at between 30,000 and 32,000.

Sina Weibo spokesman Mao Taotao said the company had yet to determine the number of infected accounts.

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